Refining of oils



Mareh 23, 1943.

R. P. FERGUSON REFINING oF`oIL Filed April 1, 1941 Q/ff ZONE

PRIMARY ZONE) CLAY ru T152/ ZONE #En v-/Nc zoNE TREA TEP The present operation may be employed when utilizing conventional decolorization clays. It is, however, particularly effective when acid treated clays such as those sold under the trade name of Super Filtrol are employed. The quantity of clay utilized will depend upon the character of the feed oil and the concentration of the color bodies in the oil. However, the amount of clay used is below about 1 pound of clay per gallon of oil, generally from about 0.1 to 0.7 pound perv gallon of oil.

The temperature, likewise, may be adjusted depending upon the particular clay employed and the character of the oil being treated. However, in general it is preferred to` Contact the oil and clay at a temperature in the range from about 300 F. to 600 F., preferably at atemperature in the range from about 400 F. to 550 F. In general the treating temperature is from about 25 F. to 50 F. below the flash point of the oil being treated. The time of contacting between the oil and clay at the elevated temperature before adding the alkaline reagent likewisey may vary considerably depending upon general operating conditions. It is preferred that the oil and clay be held at the elevated temperature for a time period of from 2 to 30 minutes, preferably for a time period of from 5 to 10 minutes before adding the alkaline reagent.

The amount of alkaline reagent added likewise'will vary and be a function of general 0perating conditions. The quantity employed will vary in the general range from 0.05 to 1.0 pound of alkaline reagent per gallon of oil. It is preferred to use from 0.05 to 0.25 or 0.5 pound of alkaline reagent per gallon of-oil. After the addition of the alkaline reagent it is desirable that the entire mixture be held at the elevated tem- -perature for a time period in the range from Vnot be construed as limiting the same in any manner whatsoever:

Example 1 A petroleum oil boiling in the lubricating oil boiling range secured as a ranate in a solvent treating operation and having a gravity of 32 A. P. I. was treated at a temperature of 425 F. with clay and soda lime in several operations with the results as follows:

. Resulting Operation gcallgnpirl Soda-lime per gallon oil n Vproduct 0. 5# None 9.0 0.5# 0.25 introduced with clay--. 3.8 0. 5# 0.25 introduced after reaching 425 F 9. 0

It is to be noted that in operation 1, in which lubricating oil was contacted utilizing only clay, the resulting' product had a Robinson color of 9.0.

' However, in operation 2, in which the clay and paired. In operation 3, wherein the oil was contacted with clay followed by the addition of soda lime, the decolorizing eiiiciency of the clay was not affected.

Example 2 A petroleum oil boiling in the lubricating oil boiling range was treated with 20 pounds of 98% sulfuric acid per 100 gallons of oil. The oil after removal of the acid sludge was clay contacted at 425 F. employing a number of operations.

The results attained in these operations are as soda lime were utilized simultaneously, the de,

colorizing efficiency of the clay was materially im..

In other operations a heavy residual stock segregated from an acid treating operation utilizing pounds 98% sulfuric acid per 100 gallons of oil was treated at 525 F. with the following results:

v Colo o Neut. Oper Clay v sfda" tag tag No.1ng. ation Condltlons #/gallon #/lglln Robin- 135%' KOH son hr. at gm' any Vadded M 0.3 2.6 0.30 2....- Clay and sodav lim? addedlsiy y mu taneous y.. 0. 2 1. 7 0.08 may added- 4 a then soda-lime after 5 min. at contact tem- 1 Y Y perature r0.3V K 2.6 0.11

Eample-4 Respective portions'of a'petroleum oil boiling in the lubricating oil boiling range and having a viscosity Saybolt of 139 at '100 F. were treated by the following operations:

taoo1or' Neat. Oper- C Clay Sda tag tag No mg ation Ondltons #/gaudn lime Robin- Rohm' KH #/gallon son 16 l son hr. at gm',

Original Oil v 2.5 Acid treated 30 pounds of 98% acid per gallons of oil.-. Black l 'f 1----- C1ay at 300 17 3. 5 1. 85 2---.- Caustic treated 40 Baum, thelili dwater was e 10.7 6.7` 0.78 3----- Treated 40 Y Baume canst1c, then clay..- 34 10.7 5. 5 1. 40 4...-- Clay,thencaust1c. V4, $4 16. 8 11. 1 0.38

Eample 5 Respective portions of a petroleum oil boiling in the lubricating oil boiling range and having a viscosity Saybolt of 675 at 100 F. were treated by the following operations:

Colloho Color Neut. Sodatag Opcr- Clay tag No.mg. ation Commons #/gauon hm@ nobin- Rohm' KoH/ l #/gallon son son 16 gm hr. at 210 F.

Original oil 2. 04 Acid treated 40 pounds of 98% acid per 100 gallons of oil... Black 1..... Clay at 380 F... M 15. 4 8.0 1.14 2 Caustic treated 40 B aum, then Water 11.8 0.3 0. 26 3-.... Caustic treated 40 Baume, then clay 14 11. 3 9. 4 l. 2G 4..... Clay, then caustic M M 12.5 10.0 0. 18

Example 6 Respective portions of a petroleum oil boiling in the lubricating oil boiling range and having a viscosity Saybolt of 1687 at 100 F. were treated by the following operations:

tot? Color o Neut Sodatag Oper- Conditions Clay Tm tag R b. No.1ng. ation #/gauon 1 Robin- 0 m KOH #/gallon son slim 16 gm/ r. at 210 F.

Original oil 1.46 Acid treated 40 pounds of 98% acid per 100 gallons of oil.-. Black 1...-- Clay at 400 F.-. M 10. 4 2. 2 0.88 2..... Caustic treated 40 Baume, then water-- 12.0 10.5 0.80 3-.... Caustic treated 40 Baume, then clay M 9. 7 6. 4 0. 69 4..-.. Clay, then caustic Z4 M l2. 8 10.7 0.05

From the above it is apparent that treatment of an acid oil With clay alone materially improves the color but does not give an oil of low neutralization value or of stable color. Treatment with an alkaline reagent alone produces an oil of 10W neutralization value but poor color and color stability. By suitable combination of these procedures in a specific manner as disclosed by my invention, oils of low neutralization value, good color and good color stability may be obtained.

What I claim as new and Wish to protect by Letters Patent is:

1. Process for the rening of petroleum oil Which comprises treating said petroleum oil with a mineral acid to remove objectionable compounds therefrom, separating the acid treated oil, and heating the same in the presence of a color adsorbent to a temperature in the range from about 350 F. to about 650 F.. holding the oil clay mixture at this temperature for a time period in the range from about 5 to about 30 minutes, then adding an alkaline reagent, cooling the mixture and separating the color adsorbent and alkaline reagent therefrom.

2. Process as dened by claim 1, in which said color adsorbent is an acid treated clay, and said alkaline reagent is Soda lime.

3. Process for the refining of petroleum oils boiling in the lubricating oil boiling range, which comprises contacting said oil With sulfuric acid, separating the treated -oil from the acid sludge and adding clay thereto, heating the oil-clay slurry to a temperature in the range from about 350 F. to 650 F., and holding the slurry' at said temperature for a -time interval of about 5 to 10 minutes, then adding an alkaline reagent and holding the mixture at said elevated temperature for a time period of from about 2 to 5 minutes, cooling the mixture and separating the alkaline reagent and clay therefrom.

4. Process as defined by claim 3, in which said oil slurry is heated to a temperature in the range from about 450 F. to 550 F., said clay is an acid treated clay, and said alkaline reagent comprises soda lime.

ROBERT P. FERGUSON. 

